IndicesCAT Previous-Year Questions

26 previous-year questions on Indices from CAT, with full solutions. Practise free — check answers as you go; sign in to save your progress.

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26 questions

Indices · CAT PYQs

CAT 2024 Slot 1 · QA
Q1.

The sum of all real values of k for which (18)k × (132768)12 = (18) × (132768)1k, is

CAT 2024 Slot 2 · QA
Q2.

If m and n are natural numbers such that n > 1, and m = 225 × 340, then m - n equals

CAT 2024 Slot 3 · QA
Q3.

If 3a = 4, 4b = 5, 5c = 6, 6d = 7, 7e = 8 and 8f = 9, then the value of the product abcdef is

CAT 2023 Slot 2 · QA
Q4.

The sum of all possible values of x satisfying the equation 24x2 - 22x2+x+16 + 22x+30 = 0, is

CAT 2023 Slot 2 · QA
Q5.

Let a, b, m and n be natural numbers such that a > 1 and b > 1. If ambn = 144145, then the largest possible value of n - m is

CAT 2023 Slot 3 · QA
Q6.

Let n be any natural number such that 5n-1 < 3n+1. Then, the least integer value of m that satisfies 3n+1 < 2n+m for each such n, is?

CAT 2022 Slot 3 · QA
Q7.

If (75)3x-y = 8752401 and (4ab)6x-y = (2ab)y-6x, for all non-zero real values of a and b, then the value of x + y is

CAT 2021 Slot 2 · QA
Q8.

For all possible integers n satisfying 2.25 ≤ 2 + 2n+2 ≤ 202, the number of integer values of 3 + 3n+1 is

CAT 2021 Slot 3 · QA
Q9.

In ‘n’ is a positive integer such that (107)(107)2...(107)n > 999, then the smallest value of n is

CAT 2020 Slot 1 · QA
Q10.

The number of real-valued solutions of the equation 2x + 2-x = 2 – (x – 2)² is

CAT 2020 Slot 1 · QA
Q11.

If x = (4096)7+4√3, then which of the following equals 64?

CAT 2020 Slot 3 · QA
Q12.

If a, b, c are non-zero and 14a = 36b = 84c, then 6b(1c-1a) is equal to

CAT 2020 Slot 3 · QA
Q13.

How many pairs (a, b) of positive integers are there such that a ≤ b and ab = 42017?

CAT 2019 Slot 1 · QA
Q14.

If m and n are integers such that (√2)19 34 42 9m 8n = 3n 16m (64)1/4, then m is

CAT 2019 Slot 1 · QA
Q15.

If 5.55x = 0.555y = 1000, then the value of (1/x) − (1/y) is

CAT 2019 Slot 2 · QA
Q16.

If 5x - 3y = 13438 and 5x-1 + 3y+1 = 9686, then x + y equals

CAT 2018 Slot 1 · QA
Q17.

Given that x2018y2017 = 1/2 and x2016y2019 = 8, the value of x2 + y3 is

CAT 2018 Slot 2 · QA
Q18.

If N and x are positive integers such that NN = 2160 and N2 + 2N is an integral multiple of 2x, then the largest possible x is

CAT 2017 Slot 1 · QA
Q19.

If a and b are integers of opposite signs such that (a + 3)2 : b2 = 9 : 1 and (a - 1)2: (b - 1)2 = 4 : 1, then the ratio a2 : b2 is:

CAT 2017 Slot 1 · QA
Q20.

If 92x–1 – 81x-1 = 1944, then x is

CAT 2017 Slot 2 · QA
Q21.

If 9x-12 - 22x - 2 = 4x - 32x - 3, then x is

CAT 2006 · QA
Q22.

If x = −0.5, then which of the following has the smallest value?

CAT 2006 · QA
Q23.

What are the values of x and y that satisfy both the equations?

20.7x . 3−1. 25y = 8627

40.3x . 90.2y = 8 . (81)1/5

CAT 2002 · QA
Passage / Data

Answer the following question based on the information given below.

There are 11 alphabets A, H, I, M, O, T, U, V, W, X, Y. They are called symmetrical alphabets. The remaining alphabets are known as asymmetrical alphabets.

Q24.

If pqr = 1 then 11+p+q-1+11+q+r-1+11+r+p-1 is equivalent to

CAT 1997 · QA
Passage / Data

Answer the next 3 questions based on the following information.

There are 60 students in a class. These students are divided into three groups A, B and C of 15, 20 and 25 students each. The groups A and C are combined to form group D.

Q25.

Which of the following is true?

CAT 1991 · QA
Passage / Data

Use the following information:

Prakash has to decide whether or not to test a batch of 1000 widgets before sending them to the buyer. In case he decides to test, he has two options: (a) Use test I ; (b) Use test II. Test I cost Rs. 2 per widget. However, the test is not perfect. It sends 20% of the bad ones to the buyer as good. Test II costs Rs. 3 per widget. It brings out all the bad ones. A defective widget identified before sending can be corrected at a cost of Rs. 25 per widget. All defective widgets are identified at the buyer’s end and penalty of Rs. 50 per defective widget has to be paid by Prakash.

Q26.

273 – 272 – 271 is the same as